An ordinary portable device may refer to an electronic device or a communication device which allows a user to enjoy not only a communication function, such as a voice communication or a message transmission, but also multimedia services such as storing various information items, playing a game, and watching a video while the user carries the device. The portable device may include, for example, a smart phone, a tablet Personal Computer (PC), a palm PC, a portable game machine, a video/music file reproducer, a cellular phone, or a notebook PC.
Presently, with only one portable device, it becomes possible to execute not only a communication function such as voice communication, but also a banking function, such as a micropayment, and various other functions or services, such as game/multimedia services. Originally, portable devices merely provided a voice communication service or a message transmission service. However, with the development of electronic/communication techniques, portable devices have been gradually miniaturized, slimmed, and lightened. As such, not only have the communication functions been incorporated into the portable devices, but also, for example, a security function enabling banking transactions, a multimedia function for enjoying a game or a video image, and a simple business transaction function including the transmission/reception of Internet information and/or mail have been incorporated into the portable devices.
Accordingly, displays mounted on the portable devices have also been improved, and various display devices have been developed. As the display devices, for example, a Liquid Crystal Display (LCD) device, a Plasma Display Panel (PDP) device, a Field Emission Display (FED) device, an Electro Luminescence Display (ELD) device, and an Organic ELD (OELD) have been developed, and display devices are still developed in a direction of pursuing thinning, lightening, and low power consumption.
In addition, flexible or foldable display devices have been developed, and curved-type display devices are also increasingly being employed in Televisions (TVs), monitors and wearable devices.
The above information is presented as background information only to assist with an understanding of the present disclosure. No determination has been made, and no assertion is made, as to whether any of the above might be applicable as prior art with regard to the present disclosure.
However, a flexible device employing a flexible display device is limited in bent angle or folded angle due to a difference in elongation generated when it is curved, bent or folded. If a structure capable of removing the above-mentioned difference in elongation appears, flexible devices may become more prolific.